Brazing furnace construction



- Feb; 24, 1959 Filed Npv. 20, 1953 c. w. MORRISON 2,874,949

BRAZING FURNACE CONSTRUCTION 2 Sheets-Sheet l Fig.2

IN VEN TOR.

: CLYDE 14 MOQR/SO/V ATTORNEY v Feb. 24, 1959 c, w MORRISON 2,874,949

BRAZING FURNACE CONSTRUCTION Filed Nov. 20, 1955 *2 Sheets-Sheet 2 uQ-A19 L '23??? -f; :"r

IN VEN TOR.

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ATTORNEY United States Patent-Of BRAZING FURNACE CONSTRUCTION Clyde W.Morrison, La Salle, Mich.

Application November 20,1953, Serial No. 393,363 8 Claims. (Cl. 263-40)This invention relates to high temperature furnaces, but particularly tohydrogen brazing furnaces.

Ordinarily furnaces of this type are constructed of masonry, insulatingfire brick' being used for the walls.

of the heating chamber. In the event of damage, breakage or fracturingof the walls of the heating chamber, it is necessary for the furnace tobe shut down for quite a long period of time sufiicient to allow coolingto a degree enabling the damaged portion to be repaired,- such as thereplacement of the insulating brick by properly cementing them in placeafter removal of the damaged ones. Not only is this costly from therepair standpoint, but the extended time during which the furnace is outof operation is even more costly.

It is a desideratum to obviate the above difficulties and objections andto produce a furnace, the parts of which are subject to fracture, arereadily accessible and can be quickly replaced without the necessity ofcementing fire brick or taking the time to cool down the furnace as hasheretofore been imperative.

Another object is to produce a furnace of the above type having thenovel features of construction and arrangement hereinafter described.

Other objects and advantages of the invention will hereinafter appear,and for purposes of illustration but not of limitation, an embodiment ofthe invention is shown on the accompanying drawings, in which:

Figure 1 is a transverse sectional view on the line 1-1 of Figure 2,showing the furnace, a portion of the metal plate being broken awayfonpurposes of clarity and the wire mesh chain conveyor for progressingarticles through the heating chamber being omitted;

Figure 2 is a vertical sectional elevation substantially on the line 2-2of Figure l and diagrammatically showing the wire mesh chain conveyorwith drive wheel on the outside of the furnace; and

Figure 3 is an enlarged perspective view of one of the blocks formingthe side walls of the heating chamber and showing fragments of thetransverse bars socketed in the block as well as tubes supported on thetop of the blocks.

The illustrated embodiment of the invention comprises a hydrogen brazingfurnace having a sheet metal shell of substantially rectangular form.The top of the shell is open but is closed by a sheet metal cover 13.The bottom of the shell is closed by a plate 11 which rests upon a pairof U beams 12 thereby elevating the furnace from the supporting floor.Within the shell and resting upon the sheet metal bottom wall 11 are anumber of courses of insulating fire brick suitably cemented togetherforming a masonry structure indicated at 14. Supported on the masonrystructure 14 are two vertical walls of cemented refractory blocks 15which are spaced laterally from each other and which terminate asubstantial distance short of the sheet metal cover 13.

Disposed between the upright masonry walls 15 and the side walls of theshell 10 is a quantity of suitable loose insulating material 16,substantially filling the space to afford the proper degree of heatinsulation for retaining the heat within the heating chamber andmaintainoutwardly extending integral projections 20. Each projection 20has a flat top 21 and a socket or notch 22 open at the upper end and adownwardly and inwardly tapering bottom wall 23. It will be understoodthat the projections 20 on the blocks of each of the two rows, faceeachlother, and extending from one block to its opposite, are ceramicbars 24 of suitable ceramic supporting material, the ends of the barsresting in the 'sockets 22. Each of the bars has a fiat bottom andparallel side walls with a rounded top wall. Thus the lower series ofbars 24 form the support for hearth plate and the top row of bars 24form the support for top heating element.

Resting on the ledges 18 are the end portions of elon gate tubes 25which are of suitable ceramic insulating or refractory material. Thetubes 25 form the support for loose insulating material 26 which isplaced on top,

providing a seal for the top of the heating chamber.-

Any suitable heat insulation material which can, for example, beshoveled in, is suitable for this purpose.

Thus the tubes 25 are placed close enough together so as to supportandretain the insulating material 26 in place.

From the above, of failure or damage to one or another of the blocks 17,the top 13 is removed and the insulating material 26 shoveled out and byremoving the tubes 25 or a portion of them, the failure can be readilylocated and when located, the damaged block can be lifted out andreplaced by a new one without putting the furnace out of operation forany extended period of time. Since no masonry is necessary for thispurpose, the time required for effecting the repair is reduced to aminimum. Similarly access can be had to one or more of the bars 24 whichhad failed for one reason or another.

The entrance to the heating chamber is indicated at B, and the exit at Aand in these regions different sized refractory blocks are employed andthese may be freely laid in place and as shown, similar tubes 25 aredisposed in this region. At the inlet blocks of ceramic refractory.material are loosely arranged to provide a flue 30 for the outlet ofcombustion gases or products of combustion. In this instance, a hearthplate 27 rests on the 1 lower series of bars 24, and for conveyingmaterial through the heating chamber, an endless conveyor 28 trainedover suitable drive wheels 29 and driven in any suitable manner, isprovided.

It is to be understood that the chamber may be heated by suitableelectrical units arranged above and below the bars 24 respectively, i.e. an electrical heating unit below the lower row of bars 24 and anotherelectrical heating unit above the upper series of bars 24. These are notillustrated nor is the means for introducing and creating the hydrogenatmosphere, since these devices are well-known to those skilled in thisart and a detailed description and illustration thereof are not regardedas necessary.

From the above description, it will be manifest that the importantfeatures of the invention reside in the provision of loosely arrangedremovable blocks which can be replaced in the event of failure, breakageor the like without shutting down the furnace for any extensive PatentedFeb. 24, 1959.

it will be manifest that in the eventperiod of time and'withoutemploying any masonry. The tubes which support the insulation also canbe replaced readily since they are simply loosely arranged and by bytaking out the loose insulation arranged above the,

work since no masonry is required to effect such repairs.

It is to be understood that numerous changes in details of construction,arrangement and choice of materials may be effected without departingfrom the spirit of the invention especially as defined in the appendedclaims.

What I claim is:

l. A furnace of the "class described, comprising aplatform and uprightlaterally spaced fixed masonry walls of insulating refractory materialhaving flat inside surfaces, and means forming a treating chamberbetween said spaced walls, said chamber forming means including ahorizontal row of insulating refractory blocks of similar constructionarranged contiguous to each other, said blocks being adjacent to andfree from the inside of each wall, each block being loosely mounted,whereby one or more damaged blocks can be readily lifted vertically andreplaced without resorting to cementing the blocks together, a row ofloosely mounted independent insulating members separate from each otherand spanning the upper ends of said blocks and resting freely on same,thereby to provide the ceiling for the combustion chamber, and looseinsulating material covering said insulating members whereby access toone or another of the blocks is had by removing portions of theinsulating material and adjacent insulating members.

'2. A furnace of the class described, comprising a base, a pair ofupright laterally spaced permanent masonry walls, a row of uprightblocks of insulating refractory material on the inside of each permanentwall, each block being loosely mounted and free of adjacent blocks, aloose spacer member extending transversely between corresponding blocksof each row, means on each upright block for receiving an adjacent endof a spacer member, transverse closely arranged insulating membersspanning thetops of said blocks, and loose insulating material coveringsaid transverse members, whereby removal of one or more of said blockscan be had by removing the loose insulating material and the adjacenttransverse members and then lifting out the desired block or blocks.

3. A furnace as claimed in claim 2, comprising a pair of verticallyspaced supporting ledges on the inner face of each block, and barsconstitutingthe spacer means resting on corresponding ledgesrespectively, thereby to extend transversely between the spaced rowsupright blocks.

4. A furnace as claimed in claim 2, in which the insulating member'scomprise elongate tubes, arranged contiguously to each other.

5. A furnace of the class described comprising a base,

a pair of upright laterally spaced permanent masonry walls, a row ofupright blocks of insulating refractory material on the inside of eachpermanent wall, each block being loosely mounted and free of adjacentblocks, each block having on the inner face thereof a pair of verticallyspaced sockets open at the top, bars extending from the sockets of oneblock to corresponding sockets of the opposite block and having theirend portions loosely resting in sockets, a row of contiguous tubesresting freely on the top of said blocks, and insulating material onsaid "tubes.

6. A furnace of the class described comprising a base, a pair of Uprightlaterally spaced permanent masonry walls, a row of upright blocks ofrefractory material on the inside of each permanent wall, each blockbeing loosely mounted and free of adjacent blocks, each block having onthe inner face thereof a pair of vertically spaced sockets open at thetop, bars extending from the sockets of one block to correspondingsockets of the opposite block and having their end portions looselyresting'in sockets, and cover means extending from one row 'of uprightblocks to the other end loosely resting on the top portion of suchblocks.

7. A furnace of the class described comprising a base, a pair of uprightlaterally spaced permanent masonry walls, a row of upright blocks ofrefractory material on the inside of each permanent wall, each blockbeing loosely mounted and free of adjacent blocks, each block having onthe inner face thereof a pair of vertically spaced sockets open at thetop, and bars extending from the sockets of one block to correspondingsockets of the opposite block and having their end portions looselyresting in sockets.

8. A furnace of the class described comprising a base, a pair of uprightlaterally spaced permanent masonry walls, a row of upright blocks ofinsulating refractory material on the inside of each permanent wall,each block being loosely mounted and free of adjacent blocks, each blockhaving on the inner face thereof a pair of vertically spaced supportswith upwardly open supporting surfaces, bars extending from the supportsof one block to corresponding supports of the opposite block and havingtheir end portions loosely resting on said supports, and cover meansextending from one row of upright blocks to the other and looselyresting on the top portion of such blocks.

References Cited in the file of this .patent UNITED STATES PATENTS1,670,606 Bowen May 22, 1928 1,741,680 Davey Dec. 31, 1929 2,552,648Poland IMay 15, 1951 FOREIGN PATENTS 849,145 France Aug. 7, 1939 255,479Great Britain Apr. 21, 1 927

